You have to first prove that it is not going to do more harm than good. And without knowing what sort of harm AI's do - it's all theoretical at the moment - any regulation is merely speculating a harm, and the cost of prevention might be high (or stifling).
ABS and ESP in cars came _after_ harm was shown. And so is emission controls, and crash-related safety measures and testing/certification.
> And then they forbid stuff which can cause cancer…that was smart!
which makes sense, as those stuff has been shown to cause cancer.
In other words, harm has to be shown, rather than speculated, before regulation is desirable.